Samsung Electronics Co. is making another run at that perennial technogeek dream, the wrist communicator, with plans in the next few months to unveil a smartwatch that works as a stand-alone phone.

Samsung's watch-phone will be able to make and receive calls without being tethered to a smartphone, something most smartwatches on the market now can't do, according to people familiar with the company's plans. It will also take photos, send email and come with GPS, Bluetooth and a heart monitor, the people said—a suite of...